Iphone 12 wifi/bluetooth greyed out

The wifi and bluetooth buttons in settings are disabled. It first happened a week ago and I just turned the phone off and on again and they both started working again. A few days ago it happened again and turning it off/on didn't help so I did an update which then fixed the problem for two days. It's now stopped working again and there is no update I can do, I have tried resetting the network settings and rebooting with airplane mode turned on and nothing I do will enable wifi or bluetooth. I think it is a software problem.